This article is ignorant and extremely biased. The first paragraph totally ignores the fact that consumer behavior radically changes when the price of a good hits zero. People who would otherwise not listen to Radiohead downloaded it -- just because it cost them nothing. The assumption made is that everyone who downloaded it would have ran out and bought it in stores, which is a terribly flawed premise. Did they listen to it once, or did they listen to it a thousand times? They may or may not have bought it, but it's impossible to tell.
I feel as though they did fantastic, considering people had the choice to get the exact same good for free or not free, and an amazing 38% of them paid for it. I'd feel safe betting that if other artists could pull this level of revenue off, they'd be beating the deep cuts taken by the record industry.